You lost me in the first paragraph - you’re boyfriend is medicated or your other friend is medicated? This whole thing sounds like a trainwreck is about to happen. Trust is big in a relationship (so I hear) and there ain’t none here. That said I’m not one to openly condemn polygamous relationships because I’m just enlightened and modern. You are going to have to decide on your road to happiness - your secret makes me wonder if anybody can rely on you. Good luck